In general, a washing machine is an apparatus that washes laundry using an interfacial separation action of detergent or a current of washing water.
The laundry is put into the tub of the washing machine, and then water and detergent are supplied. When the outer tub is filled with water to a certain level, the inner tub starts to rotate to wash the laundry.
A water spraying unit may be installed in the washing machine. The water spraying unit has a function of circulating washing water from the outer tub and spraying the washing water into the inner tub. As the water spraying unit sprays the washing water into the inner tub while washing the laundry, the laundry is wetted more quickly, thereby improving the washing efficiency of the washing machine.
In the prior art, the water spraying unit is configured to spray the washing water into the inner tub, using an independent pump or water pressure of the water supplying unit. Therefore, there may be a limit to increasing the pressure for spraying the washing water.